In a DC-driven electric motor system, such as a hybrid vehicle system with one or more electrical motors, the power of the system is typically increased by enlarging the motor, adding additional magnets to the motor, or boosting the available DC voltage with, for example, a conventional boost DC-DC converter. However, a larger motor typically takes up additional space, additional magnets generally provide additional complexity and weight, and boosting the available DC voltage generally burdens the motor with a higher current rating. Hence, extra power provided by conventional boosting techniques is typically offset by one or more disadvantages.
More recently, inverter circuits have been designed to increase the power provided within an electric motor system. A conventional six-switch, three-leg inverter topology, for example, can increase the power of a system that includes one or more three-phase motors where the DC link is connected across a line-to-line portion of the three-phase motors. Even this topology, however, typically has limitations on its ability to increase available power and/or to decrease the current rating of the inverter.
Accordingly, it is desirable to provide an improved inverter topology for obtaining boost power from a multi-motor system without adding complexity to the system or increasing the motor size. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.